Educational cartoon use has been typically centered around the political and social sciences where students analyze political satire and various current issues.  This talk demonstrates how scientifically-themed cartoons and humor can be used in geology (in addition to other sciences) to determine how your students may be perceiving a concept as well as a tool to promote critical thinking.  The basic premise is that 1) students must understand the illustrated scientific concepts in order to comprehend the message of the cartoon or comic, and 2) students are generally less intimidated and self-conscious of their answers if challenged with a cartoon. Cartoons and comics may be used in essay-style exam questions, in-class individual and group activities, and homework exercises.  Creative or artistic students can even produce their own original cartoons.  Collecting a ‘critical mass’ of geologically-themed cartoons is relatively easy and one may begin by searching in your local newspaper’s comics, in a bookstore, and by searching comic-specific websites online.  Geologically-related comics have been published in comics such as The Far Side (G. Larson), B.C. (J. Hart), Frank and Ernest (B. Thaves), and Off the Mark (M. Parisi).  Using cartoons in the science classroom promotes creativity and encourages critical thinking, while giving instructors a tool to track student perceptions and critical thinking skills.  Limited cartoon samples will be available.